public class demo5 {
    public static void main(String[] args) {
        char a='A',b='B',c='C',d='D',e,f;
        e=a;
        a=d;
        d=e;
        f=b;
        b=c;
        c=f;
        System.out.println(a);
        System.out.println(b);
        System.out.println(c);
        System.out.println(d);




    }
}
